As the stereoscopic display technology gets widely used, the stereoscopic display devices are required not only able to display three-dimensional images (3D), but also able to display two-dimensional images (2D), e.g., text and pictures, at the viewer's discretion. As shown in FIG. 1, a conventional stereoscopic display device includes a display panel 2′ and a plurality of liquid crystal lenses 1′ disposed on the light emitting side of the display panel 2′. The display panel 2′ provides a left view image and a right view image with a parallax between the two images. Separated by the liquid crystal lenses, the left view image is presented to viewer's left eye and the right view image is presented to viewer's right eye. The viewer's brain forms the 3D image by perceiving the parallax between the two images.
As shown in FIGS. 1 and 2, the liquid crystal lenses 1′ include a first substrate 11′ and a second substrate 12′ facing each other. A liquid crystal layer are sandwiched between the first substrate 11′ and the second substrate 12′ and a plurality of spacers 14′ are placed between the first substrate 11′ and the second substrate 12′ to support the thickness of the liquid crystal layer. A plurality of first electrodes 15′ is disposed in parallel with each other on the first substrate 11′. Adjacent first electrodes 15′ are separated by a certain distance. A plurality of second electrodes 16′ is disposed in parallel with each other on the second substrate 12′. Adjacent second electrodes 16′ are also separated by a certain distance.
A plurality of first voltages and a plurality of second voltages are supplied to the first electrodes 15′ and the second electrodes 16′ respectively. The differences between the first voltages and the second voltages produce the driving electric field between the first substrate 11′ and the second substrate 12′, driving the liquid crystal molecules 13′ in the liquid crystal layer to rotate at various angles. As such, a plurality of liquid crystal lens units 17′ is formed and arranged in array between the first substrate 11′ and the second substrate 12′. The plurality of liquid crystal lens units 17′ separates the polarized light emitted from the display panel 2′ into a left view image to be viewed by viewer's left eye and a right view image to be viewed by viewer's right eye. Thus, the stereoscopic display effect is achieved.
As shown in FIG. 3, when the stereoscopic display device 600 is used to display 2D images, the voltages supplied to the liquid crystal lenses 1′ are cut off. As such, no electric field is produced between the first substrate 11′ and the second substrate 12′. Due to the substantial difference in refractive index between the spacers 14′ and the liquid crystal molecules 13′, the polarized light emitted from the display panel 2′ is refracted when passing through the spacers 14′, causing bright spots surrounding the spacers 14′ visible to viewer's eyes. Such bright spots may impact the viewing experience and cause discomfort to the viewer's eyes.
Another type conventional stereoscopic display device includes a display panel and a liquid crystal lens grating. The display panel includes a plurality of pixel units and a plurality of black matrices configured among the pixel units. The liquid crystal lens grating includes a plurality of liquid crystal lenses and a plurality of spacers positioned corresponding to the positions of the black matrices on the display panel. However, such black matrices on the display panel may affect the display effect. In addition, the black matrices may be unable to completely cover the spacers and the bright spots surrounding the spacers can still be visible to viewer's eyes.
The disclosed stereoscopic display device is directed to solve one or more problems set forth above and other problems in the art.